Vehicles manufactured after 1996 in the United States are required to implement OBD-II, an on-board diagnostics reporting capability.1 Luckily the standard requires a specific connector, placement, pinout, and permits a set of signaling protocols.
My Civic implements a few of these protocols, but the one of interest is Controller Area Network (CAN). One way to interact with your vehicle is using an ELM327-based2 device. These affordable devices abstract away the complexity of OBD-II behind a device with an AT command set.